Why does certain characters draw horribly, horribly wrong in Windows?

Odd characters:

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Question: Why does these characters draw so odd when you look at them in Windows*?

Here's a snippet from Outlook for you lucky bastards who aren't forced to use Windows:

Related:What's the character encoding used?

*Windows as in the OS. Applications drawing text using GTK+ and the likes doesn't show these like something out of an LSD-trip gone wrong.